Casey;
Apology accepted, and it does appear that I misread what the gun was going to be used for. For some reason I was under the impression you may also use it as a huntin sidearm also and self defense gun.
You mentioned that you will be using it as a duty firearm while working with AZGFD, and that game dept. does issue the Sig 226 as their duty sidearm.
If the dept. only allowes the Sig, then your choice has been made for you. If they allow other duty firearms, as my dept. did, then you have some leeway for your gun.
I am not that familar with the XD-40 and can not give you any honest opinion about that pistol. I am very familiar with the Glocks and Sigs though my past duties as a firearms instructor, dept. armour, and gunsmithing. My oldest Son is the dept. armour for his police dept. and completed the Glock armour school due to the Glock being their issued pistol. He loves the glock.
You could go wrong with either the Sig or Glock. Both are very reliable. If I remember correctly, The Sig was barely beat out by the Berretta during the military trials for a new pistol to replace the 45ACP.
My experience has shown the Sig has a slight advantage over the Glock for accuracy, but the Glock is accurate enought for combat type use. I feel that the Glock has a better trigger then the Sig due to my personal feelings of not liking a double-single action trigger that the Sig, Berretta has. I am a old Colt 45 ACP single action trigger fan.
The Sig has shown to be very reliabe, but the Glock has a history of going 35000-40000 rounds without any parts breaking.
Both of these guns are a very good choice for duty and home defense work. I would advise you to find a place, maybe a indoor shooting range, where you can try both guns out, and maybe others, then go with the gun that you feel most comfortable with.
As for price, it should not enter the picture when it comes to a firearm that you will be betting your life, or family member's life, on. Get the gun you want and can shoot the best with. If you have too, try to make payments or take out a loan if the gun you want is beyond your present means. I did just that when I purchased my first duty gun in 1974.
You mention having a 357 mag. That caliber loaded with hot 125 grain HP,1300-1350 FPS, is the number 1 manstopper in hundreds of recorded police shootings. Sig has come out with a 357 auto round that duplicates the revolver performance. Now I have given another pistol-caliber option for you to decide on, I wish you good luck in your quest.
RELH